Fuel regulator for engines



May 18,1937- v A. SCHWEIZER 2,080,746

FUEL REGULATOR FOR ENGINES Filed March e, 19:55

Patented May 18, 1937- UNITED STATES FUEL REGULAT OR FOR ENGINES Alfred Schweizer, Stuttgart, GermanyQassignor to Robert Bosch Aktiengesellschaft, Stuttgart,

Germany Application March 0, 1935, serial No. 9,003

In Germany May 22, 1934 4 Claims.

This invention relates to the regulation of the fuel supply for internal combustion engines and more particularly to an arrangement for the regulation of the fuel supply for anautomotive 5 Diesel engine of the type provided with a servomotor acting in conjunction with a manual regulating means for controlling the engine.

It has heretofore .been proposed to provide a servo-motor actuated by pressure dependent upon the speed of the engine for controlling the fuel supply pumps of such engines. The pressure controlling the servo-motor is commonly taken from the intake manifold, but as heretofore constructed the variation in pressure in such manifold is effective in the servo-motor only after a certain time lag. It thus occurs that when the operator opens the accelerator throttle the pressure within the manifold is transmitted to the servo-motor only after an appreciable period,

2Oproportion to the air supply and not in accordance with the requirements of the engine.

It is one of 'the objects of this invention to overcome the vabove mentioned defect and reduce as far as possible the time lag between the actuation ofthe manually-adjustable throttle valve and the resultant movement of the pneumatically operated servo-motor, and to insure that upon adjustment for greater fuel charges the servo-motor temporarily adjusts the fuel pump to give a greater injection than normally corresponds to the altered adjustment of the manually controlled regulator.

To this end it is a feature of this invention t provide means coupled with the manually adjustable regulating lmember whereby upon adjustment of the regulating member for increased injection, the pressure within the servo-motor is increasedI more rapidly than would be the case by adjustment of the regulating member alone.

Other objects and features of this invention will in part be obvious andv in `part pointed out in connection with the accompanying detailed de` scription. A

To the attainment of the aforesaid objects, the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will first be fully described in the following detailed description and then pointed out in the appended claims, reference being had to the accompanying drawing in which:

Fig. 1 shows in side elevation an internal combustion engine equipped in accordance with this invention, parts being broken away to show induring which period the fuel supply is not in terior construction; Fig. 2 shows ih connection with parts of Fig. 1, a modified form of the invention; and Fig. 3 indicates another modified form.

Referring to Fig. l, reference letter a indicates a conventional four-cylinder injection type engine. A multi-cylinder injection pump, operated by the engine through gears b, is designated at c. Fuel supply conduits d lead from pump c to nozzle holders e arranged in the cylinder heads. The fuel is led from a container, not shown, to the injection pump by means of conduit f. The amount of fuel supplied by the individual pumps may be simultaneously changed in a well known manner by adjustment of a regulating rod g common to all individual pumps. The occurrence of this change upon adjustment of the regulating rod will be described later in connection with Fig.- 2.

The end of the regulating rod g protruding at the right of the pump housing is connected to the reinforced middle part of a diaphragm h,

the rim of which is inserted between a flange on the right side wall and the pumpv housing and a box-like portion z'. A spring m is arranged in the chamber lc dened by the diaphragm h and the portion i on the opposite side of the diaphragm. The spring m acts to press the diaphragm to the left and push the regulating rod linked-thereon to the left, in whichr position the pumps areadjusted for the greatest output.

Attached to the air-intake pipe n common to all cylinders is a flanged pipe o'containing a throttle valve p shown in its closed position. A venturi 'q is positioned beyond the pressure valve in the direction of ow of the suction air, and a passage r connects the venturi at its narrowest pointwith the interior of the chamber k.

A lever s attached to the pressure valve p is connected by rods leading on one side to the manually adjustable pedal t,-and on the other side to a piston u fitting with some clearance in a cylindrical extension of the' member i. The chamber formed by this extension and in which the piston u reciprocates is connected with a bore in part i containing a slide valve v. A spring .w holds the slide valve in the position shown. In. this position the slide valve v closes .a passage :c leading to the atmosphere. A passage y connects the chamber lc with the interior of said bore. The valve o is provided with an annular groove z. 'Y

The operation of the form of the device described above is as follows: If the driver desires to increase'the speed of the engine, the accelof' the diaphragm hand regulating rod g uponv ing behind the ithrottle valve because of the suction of the engine is decreased. After a, certain -time lag the low pressure of the chamber Vk of the motor would normally adjust itself through the passage rl to the increased pressure in the] suction pipe and'thereby permit the spring to push the diaphragm center, and the regulating' rod of the injection lpump connected therewith, somewhat to the left, that is in the direction of increased fuel supply. y

In order to decrease the time lag occurring in this regulating procedure the piston uis adjusted simultaneously with the opening of the throttle valve p. thereby compressing/ the air in its cylinder so that the slide valveis' forced by this pressure to the lrgtagfhst' the force of spring w.v Upon thisZnidvement the annular groove z of the slide/ valve o registers with the passages a: and y so ythat the chamber k is--thereby connected with the outer air. The low pressure previously existing in the chamber lc is then quickly increased to that of the atmosphere. 'I'he spring m is effective at the moment to move the diaphragm and the connected regulating rocin the direction of increased fuel injection, which results in the' greatest possible fuel supply. In the" meantime, if the driverl continues to hold the foot `lever depressed, the air pressure inthe cylinder' con' taining piston u hasescaped around the loosely fitting piston. The spring w thereupon returns the slide valve to the position shown, the connection between the chamber Ic and the outer air is interrupted, andthe regulation by means of the suction in the intake manifold, which was deliberatelysuspended over a short speed-up period, is now resumed.

The second form of the invention disclosed in Fig. 2 differs substantially from therst only in` that, when the slide valve v effects connection of the regulating chamber 7c with the outer air, the? conduit 1=is closed and thereby lprevents part of the outer air owing into the chamber from beiig sucked off'through said conduit.

Fig. 2" shows the regulating rodg 'toothed and meshed with a toothediring I0. One such ring is provided for each pum'p and fastened on a shell I2 slid over the cylinder bushing I I thereof. The lower end of each shell protrudes over 'the ,cylinder bushing and is provided with slits into which project "cross pieces. M-attached tfo the accompanying pump piston', I3. Upon` turii ing' the shells, tha-pistons I3 are rotated; {This resuits in the adjustment of the control surface I5 on the pistonhead relative to the Opening I i in the stationary cylinder bushing. This adjust' ment produces-1an increase or decrease inv the effective stroke of the piston* I3 4which 'is actuated by'a cam I s Vthrough across head le. The cross" head I9 isheld in position by a groove 2l. The openings I 6 of all pump cylinders are connected to a common suction chamber 2l in the pump houslngf- In the embodiment of Fig.- 3, a rapid'actuation speeding up of the engine is attained by a piston 'housing'r This piston forces the air content of opening the pressure valve p, so that a more rapid and higher pressure increaseresults than would be possible through conduit r'alone. -In all theabove examples-the suction of the ensineis utilized to operate the servo-motor and a spring serves to eect re'turn movements thereof. It will be obvious that any other source of fluid pressure, either above or below atmospheric pressure, may be used to operate the servo-motor, provided this pressure varies in accordance/with vthe speed of the engine. Also fluidpressu're may servo-motor tojincreased speeds. Furthermore,

a brief period f maximum fuel supply is automatically provided each time the engine is manually accelerated.

Although there are herein described but three .exemplary embodiments of the invention, it will `be obvious that other modifications and embodiments within the scope of the appended claims will occur to those skilled in the art.

What is claimed is:

1. In regulators for the fuel supply of an intery nal combustion engine, a fuel supply device. a

v regulating member for varying the quantity of fuel supplied by said device, a chamber, amovable member responsive to pressure variations in said chamber, means connecting saidr movable 'member to said, regulating member, a conduit,V

connecting said chamber and thefiintake manifold of said engine, a cylinder adjacent said chamber, a piston reciprocative in said cylinder, a throttle valve in said manifold, manual means to actuate said throttle valve, means connecting said throttle valve actuating means and saidv piston to move the latter to compressthe air in.

'Said cylinder upon movement of said throttle l valve to open position, ymeans responsive to said compressed air for increasing the pressure in said chamber, and means providing a leakageof air from said cylinder ,whereby after a predetermined .time pressurein 'saidv cylinder isreduced and the pressure in said chambei-.returns todependence isam manifold.

upon pressure conditions '2. Infregulators for' the fuelsupply o1.l an interf nal combustion engine, a If uel supplydevice, va, f regulating member for varying the .quanidty,of

fuel suppliedbyv said device, a chamber, a monr-A able member in said chamberresponsive to pres? 'sure variationstherein,' means connecting said.

movable member'tc said. member. conduit connecting saidchamber and the `intakel ,manifold ol' said enginer through' which pressure in said chamber and manifold tends to equalize,

l a passage'between andthe aimese, a throttle phere, a valve controlling said in said manifold, manual means to actuatc throttle, means Abvy movel'nentf of said throttle to open positiontoopen said valve there-f' by connecting said 4with the',

andrmeans 'automanauy c1osmgak predetermined time lag.v

3.' In regulators forthefuel suppl? 0fI an inter' nal combustion engine, a fuel a'.l-

Vregulating member for varying the duantitypf fuel supplied by said fce, a c ncvf able memberin said chamber sure variations in said"chamber, a conduit' tin'sid chamber and aleman mmlfuawof said engine through which "innid chamber and manifold tends to equalize,

sage between said andthe atmospheretf. avalve' controlling both said pamgeand while closing communication between said chamber and the atmosphere, a throttle in said mani4 fold, manual means to actuate said throttle, means actuated by movement of said throttle to open position to move said valve thereby obstructing said conduit between said chamber and said manifold, and opening saidpassage between said chamber and the atmosphere, and means automatically returning said valveto normal position after a predetermined time lag.

4. In regulators for the fuel supply of an in# ternalcombustion engine, a fuel supply device, -a regulating member for varying they quantity of fuel supplied by said device, a diaphragm connected to said regulating member, a .chamber having one end closed by said diaphragm. said actuatesaid regulating means to increase the fuel supply independently of the equalization of pressure eiected through said conduit. 

